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zuz
2nd Sep 2007, 21:31
Could anyone help me with this question:When the inbound turn on a racetrack procedure is not defined by a Dme distance how is the timing calculated.Reading Pans Ops it only stipulates that the pattern can be 1,2 or 3mins in duration. Many procedures I have seen have no mention of specific timings. Thanking you all in advance.

Pub User
2nd Sep 2007, 22:04
The standard time on the outbound leg is 1 min up to FL140, an 1.5 mins above that. These timings are adjusted for wind effects.

keithl
3rd Sep 2007, 09:38
I agree with pu, but would add that 1 min is very short for a Sector 1 (parallel) entry to the racetrack. That is why the UK AIP "does not recommend" it. If a dme is not specified, then a time should be. If neither time nor dme are specified then, yes, use the standard minute - but be aware of its limitations.

the dean
3rd Sep 2007, 11:08
hi zuz,

we always use either 4 minutes from overhead the beacon ( so thats 1 minute each leg and 1 each for the two 180 degree turns...or better still and more accurate 3 minutes form 90 degrees abeam the beacon ( remember if you are setting off for drift that has to be taken into accoun when calculating the 90 degree position )..on the outbound heading +/- drift correction...therefore 1 minute ( depending on the wind correction ) out, 1 minute for the 180 degree tuirn ( 3 degrees per second rate 1 turn ) and 1 minute for back to the beacon..

ok..hope that helps...:ok:

the dean

taperlok
3rd Sep 2007, 12:10
all depends on aircraft size ( speed) and altitude. On an a300 at 14 000ft. one hold with 1min outbound leg will take +/- 6min.:cool:

TopBunk
3rd Sep 2007, 12:20
Rainboe - I agree.

I've long since forgotten the formula, but Rate 1 turns are not a concept used in heavy jet aircraft, and I believe that a 25 degree angle of bank turn will give you (in still air) less than Rate 1 (by how much I can't remember and don't care either!).

I do remember in practice (when I was flying aircraft without an FMC and auto hold pattern tracking), that I would start the stopwatch abeam the holding fix and fly an adjusted outbound heading for 1 minute +/- a wind adjustment before turning inbound, this would result in the inbound time being whatever it took to reach the fix. The total hold is usually about 5 minutes in a medium or large transport jet.

keithl
3rd Sep 2007, 12:39
From Post#4 onwards, you've been talking about the 4 minute hold. While this certainly is the minimum form of the Racetrack, the original question was about Racetracks.
Rainboe says it's all very out of date for transport aircraft, but we don't know that zuz was talking about transport aircraft. And transport aircraft may be ancient, rotary and flying Instrument Procedures.As often before, I must point out that the world is NOT entirely composed of modern, heavy jets doing "vectors to the ILS".
Where I work holding, and racetracks, using aircraft with dials and clockwork HSIs is still bread-and-butter stuff, so I take the question as real, practical and worthy of a proper answer.

keithl
3rd Sep 2007, 13:51
Rainboe - you have just implied that Commercial Helicopter pilots, because they do not fly "large passenger jets" have no place in Tech Log. Yes, there is a Rotary forum, but a question such as this applies to all professional pilots, not just Rotary and not just heavy jet.

There absolutely IS a place for Racetrack Procedures these days. It just may not apply to you, that's all.

And you still refer to Holds - do you know the difference?

fireflybob
3rd Sep 2007, 16:52
Outbound timing commences when abeam the fix. If the abeam position cannot easily be determined (ie no RMI) outbound timing starts when established on the outbound heading.

In a racetrack procedure (ie NOT holding) the outbound timing is specified - in the state AIP and instrument approach charts (Jepp/Aerad etc). These times should, of course, be corrected for wind effect.

savi
3rd Sep 2007, 16:54
For example: KRK (Krakow), RJK (Rijeka) ... . Racetrack is still alive.